1. Field of the Invention
The invention is directed to a loading device for ISO containers in a container terminal for loading and unloading ships with a container bridge, a boom which extends at the gantry frame of the container bridge over its supporting construction on the water side and on the land side, and running rails for a crane trolley with container load-carrying means provided at the boom for transporting the container from ship to pier, and vice versa, wherein the loading device is arranged below the land-side boom in the rear area of the container bridge and cooperates with container transport vehicles.
2. Description of the Related Art
German Utility Model 279 19 466 discloses a loading and unloading system for containers which uses a container bridge formed by a gantry frame. The gantry frame is supported on a traveling mechanism which is movable along the rails parallel to the pier at which the ship is docked. The gantry frame has a boom extending over the supporting construction on the water side as well as on the land side and running rails are arranged at the boom for a crane trolley which transports containers from ship to pier, and vice versa, by means of a spreader. The spreader is designed in such a way that the crane operator can make the spreader engage with or disengage from the container with automatic locking.
The productivity-determining factor in a loading and unloading device of the kind mentioned above is the time period needed by the crane trolley to alternate loads, namely, the time required for conveying the containers from one location to another and for loosening or tightening the twistlock. As is well known, these twistlocks are used for preventing slippage of the containers which are stacked one above the other when transported, particularly when transported on ships. The containers are locked together in that the twistlocks engage in openings of the fittings and the parts arranged inside the fittings are twisted. Usually, semiautomatic twistlocks which are connected to the lower fittings of a container in a forward position during loading are used. When setting the container on another container, the twistlock is automatically locked with the fitting of the lower container, so that the two containers are fixedly connected to one another.
When unloading the containers from their present location, the container is first unlocked from the container below it or from the container vehicle by personnel and the upper container is transported from ship to shore with the twistlock still located on it. However, the twistlocks must be removed before the container is placed on the surface of the pier, which is likewise carried out manually in that the personnel charged with this task reaches under the suspended container and detaches the twistlock manually. Conversely, when loading, the container is initially lifted far enough so that the twistlocks can initially be inserted manually into the lower fittings before the container is transported to its new location.
German Utility Model 297 19 466 describes the unloading and loading of the containers in two overlapping phases, in which two crane trolleys are used, the first of which transports the container from the ship to a handling platform, while the second crane trolley transports the container from the platform to the desired track on the pier surface. A vehicle stands by at the pier surface to receive the container. The two crane trolleys transporting the containers at overlapping times reduces the productive work cycle time because it has been determined that less time is required for transporting a container between the ship and platform than for transporting the container to the loading track on the pier surface, including the removal or tightening of the twistlock.
However, the known solution is disadvantageous because although the use of the second crane trolley in the container bridge increases handling capacity, it results in additional relatively high investment, servicing and maintenance costs. Further, the platform for mounting and removing the twistlocks is not suitable for the handling of tank containers or other special containers (e.g., refrigerated containers or containers for shipping automobiles). While the support surfaces for the container shown in the reference allow free access to the corner fittings, a closed container base is mandatory for this technology. However, this is not always guaranteed in the case of special containers. As a result, these containers are sorted out and must be handled separately on the pier by additional personnel.
Based on the prior art, it is the object of the present invention to increase the total loading and unloading capacity of the container bridge through economical steps and, in so doing, also to ensure safe assembly and disassembly of the twistlocks at the corner fittings.
According to the invention, the loading device comprises at least two bridge members which are movable on the ground independent from one another transverse to the longitudinal axis of the boom, and are oriented parallel to one another and to the boom. Each bridge member forms a loading station for a container and carries in the area of its longitudinal center a receiving platform for an ISO container which can be set down and picked up by load-carrying means, this receiving platform being swivelable about a vertical axis.
The proposed loading device appreciably increases the loading and unloading capacity of the container bridge. It replaces the second trolley traveling mechanism in the container bridge and makes it possible to rotate the containers by at least 90xc2x0 so that they arrive from the transporting position in the ship to the unloading position in the transporting vehicle. The at least two loading stations which are provided constitute an intermediate storage for the containers which is movable on traveling mechanisms from the loading area to the off-loading or on-loading area of the transporting vehicle.
The loading station is movable by at least one traveling mechanism on a runway or rail extending on the ground transverse to its bridge member. The rail which is preferably common to both loading stations allows an exact positioning of the loading station relative to the load receiving means of the container bridge on the one hand and relative to the traveling track of the transporting vehicle on the other hand. In this connection, the transport vehicle can be an automated driverless transport vehicle (FTV) or an automated guided vehicle (AGV). Alternatively, containers can also be transported for loading and unloading manually by straddle carriers.
According to a special feature of the invention, it is provided that every bridge member of every loading station is angled upward in an L-shaped manner and, by means of a rail traveling mechanism arranged at its upward angled end, is movable on a horizontal running rail which is arranged at a longitudinal member fastened to the supporting construction of the container bridge transverse to the boom. In this construction, the loading stations are connected in a positive engagement with the container bridge, wherein the construction allows the container bridge to move relative to the loading stations and the loading stations to move relative to the container bridge.
According to a further feature of the invention, another running rail extending parallel to the horizontal running rail is arranged at the underside of the longitudinal member and another rail traveling mechanism fastened to a tilting moment support of the loading station rolls on this running rail. This tilting moment support at the water-side rail traveling mechanism protects the loading station against tilting moments which can occur, for example, in the event of asymmetric loading of the receiving platform.
Since the relative horizontal movements between the container bridge and the loading stations must always be adapted to the different process sequences in the devices and to the respective loading and unloading conditions, another feature of the invention is a vertically acting telescoping base support arranged in the area where the angled bridge member part passes into the horizontal bridge member part. This is preferably actuated hydraulically and, in the supported state, receives the horizontal forces resulting from the sum of the rolling friction of the water-side driveless rail traveling mechanism and the rolling friction of the other rail traveling mechanisms. In this way, the loading station can be fixed relative to the ground for on-loading or off-loading a container from or to the transport vehicle. At the same time, the container bridge can be moved horizontally, e.g., for compensating heeling of a ship.
According to the invention, every rotatable receiving platform for the container is constructed for the support of different ISO container sizes and is connected via a pivoting connection to the bridge member so as to be drivable in rotation. Therefore, the receiving platform is capable of receiving any size of ISO container. By means of the pivoting connection and the rotating drive, the deposited container can be swiveled into a position rotated by 90xc2x0 in which a transport vehicle can on-load or off-load the container.
It is particularly advantageous when the receiving platform of every loading station is provided in the areas contacted by the corners of the storable ISO container with recesses for gripping and handling the twistlock connections. When the receiving platform is located in the on-loading or off-loading position in the direction of the longitudinal axes of the L-shaped bridge member, the twistlock at the corner fittings of the container can be assembled and disassembled without difficulty through the recesses by the personnel responsible for this task.
When using transport vehicles which are preferably provided with receiving devices, another feature of the invention is that transport vehicles can travel over every loading station for receiving or depositing the ISO container when the receiving platforms of the loading station are oriented in its longitudinal direction. For this purpose, the loading station has been moved into one of its end positions corresponding to the traveling tracks of the transport vehicles by transverse movement on its rail traveling mechanisms.
In a construction of the invention it is also conceivable that every loading station which is movable on the ground can be moved by rail traveling mechanisms at both of its ends on runways or rails placed on the ground and its movement sequences can be coordinated with respect to the other loading station and with respect to the horizontal movement of the container bridge. In this embodiment form, the loading stations are not connected with the container bridge in a positive engagement, but their movement sequences are coordinated with those of the container bridge. Without otherwise altering the movement processes, both rail traveling mechanisms travel on rails which are spaced apart, rather than on the girder of the container bridge. Also, in this solution it is possible for the loading stations and the container bridge to travel transversely independent from one another by providing a corresponding traveling control for the driven traveling mechanisms.
A working process for operating a loading device for ISO containers such as that described above is characterized by the following successive work steps when unloading a container ship:
Assuming a ship is being unloaded, the container suspended at the load-carrying means is lowered and deposited on the receiving platform of a loading station.
By rotating the receiving platform by 90xc2x0, the container is brought into a position in which the longitudinal axis of the container extends in longitudinal direction of the loading station.
The loading station is moved transversely into an off-loading position in which the transport vehicle takes over the container.
While the container is being transferred, the other loading station is moved transversely under the load-carrying means and is loaded with another container after the receiving platform has been rotated by 90xc2x0 relative to the longitudinal direction of the loading station.
The processes are repeated alternately so that at least one loading process and unloading process is always underway simultaneously.
A working process for operating a loading device when loading a container ship includes the following work steps:
The loading station is moved transversely into a transfer station in which the transport vehicle delivers the container.
By rotating the receiving platform by 90xc2x0, the container is brought into a position in which the longitudinal axis of the container extends transverse to the longitudinal direction of the loading station.
The container is lifted from the receiving platform of the loading station by the load-carrying means and is transported in suspended manner to the ship.
While the container is being taken on, the other transversely movable loading station is loaded with another container by another transport vehicle after the receiving platform has been rotated by 90xc2x0 relative to the longitudinal direction of the loading station.
The processes are repeated alternately so that at least one loading process and unloading process is always taking place at the same time.
A partial overlapping of the rotating movement and transverse movement would be possible for the purpose of reducing cycle time (e.g., the transverse movement is initiated after ⅓ of the rotating movement).
The novel arrangement is advantageous as an economical addition to known loading and unloading equipment because the loading device replaces a second trolley in the container bridge. Therefore, the costs of acquiring and maintaining are appreciably lower compared to conventional solutions such as those suggested in the prior art taken as a point of departure by the invention. The loading device is suitable for full automation and can also be retrofitted to existing systems. The capacity of the container terminal can be noticeably increased by the invention because two to three loading tracks can be serviced by one trolley traveling mechanism with the loading device. Time-critical sequences in terminal logistics management are prevented by the deliberate control of the container bridge in backreach by the AGVs or straddle carriers. The quantity of required container transport vehicles can accordingly be reduced.
Other objects and features of the present invention will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. It should be further understood that the drawings are not necessarily drawn to scale and that, unless otherwise indicated, they are merely intended to conceptually illustrate the structures and procedures described herein.